Fuel mixer



Sept. 26, 1944. R. A. CARROLL 2,359,022

FUEL MIXER Filed June 13, 1941 Patented Sept. 26, 1944 U N] TED STATES PATEN T O FFICE FUEL MIXER Robert A.'Carroll, West :Finl'ey, Pa.

Application June 13, 1941, Serial No. 397,309

' tion to cover or. expose the entire air opening 3 1 Claim.

This invention relates to an improved fuel mixer, and whileprimarily designed and intended for gas burners or" the type used in ranges, water heaters, heating furnaces, hot plates and the-like, it will be obvious that the device may be employed in connection with any other types of gas burnerswherein it is found to be applicable.

Important objects and advantages of the invention are to provide a fuel mixer of the character described, which will operate automatically tcregulate and coordinate the proportional mixture of air and gas as the fuel is being supplied to the burner, which may be readily installed to-a control valve already constructed as Well asvform a component part of anew valve structure, which is simple in its construction and arrangement, durable and efficient in its use, compact, and comparatively economical in its manufacture, installation, operation and maintenance,

With the foregoing and other objects in view which will appear as the description proceeds, the invention resides in the novel construction, combination and arrangement of parts herein specifically described and illustrated in the accompanying drawing, but it is to be understood that the latter is merely illustrative of an embodiment of the invention, and that the actual needs of practice and manufacture may require certain mechanical variations from the embodiment shown. It is, therefore, not intended to limit the invention to the disclosure thereof shown, out rather to define such limitations in the scope of the claims hereunto appended.

In the drawing wherein like numerals of reference designate corresponding parts throughout the several views:

Figures 1 and 2 are, respectively, top plan and side views of a fuel mixer constructed in accordance with the invention.

Figure 3 is an inner end view of the actuating member employed for operating the air control element.

Figures 4 and 5 are, respectively, top plan and side views of a modified form of air control mechanism embodying the present invention.

Referring in detail to the drawing, I denotes a conventional type of mixing tube of a gas burner (not shown), having its outer end enlarged in the usual maner to provide a mixing chamber 2. The tcp or" the mixing chamber is flat and formed with a comparatively large air opening 3. A substantially triangularly-shaped shutter 4 is pivotally connected at its inner angle or end, by means of a pivoting screw 5, to the top of the mixing chamber, and is shiftable on its connecorany proportional area or part of the latter.

A quarter-turn gas control valve 6, of any suitable construction, is disposed forwardly of and horizontally aligned with the mixing tube I. The

' gas control valve is supported in position on the gas supply pipe 'I by means of a short length of interposed pipe 8. The gas control valve includes an outwardly projecting valve -stem 9 and asuitable operating handle It fixed to the latter. The innerend of the control valve is formed with a nozzle I I, which extends through the outer wall of the mixing chamber 2 and into the latter, as illustrated .in Figure '2.

The feature of the invention resides in-an operating mechanism for'automatically and simultaneously adjusting the shutter 4 to regulate the air supply each time the valve 6 is operated to regulate the gas supply, to thereby provide an effective fuel mixture promoting the most efficient fuel combustion.

The operating mechanism comprises an actuating member I2 including a hub I3 and an inwardly projecting cam flange I4. The valve stem 9 extends through the hub 13, and the latter is adjustably secured to the former by means of a set screw I5 engaged in said hub.

The cam flange I4 is curved concentrically to the axis of the valve stem 9, and is provided with a cam slot I6, in which latter the outer end of a connecting rod I1 is shiftably engaged. The other or inner end of the connecting rod is pivotally connected, by means of a screw I8, to the shutter 4 at a point eccentrically offset relatively to the pivoting screw 5, which connects the shutter to the top of th mixing chamber 2, as shown in Figure l.

The connecting rod extends through and is longitudinally slidable in a bearing I9, which is swivelly connected to the top of a vertically disposed bracket 20. The latter is supported by and secured to the control valve 6. The swivelled connection of the bearing I9 allows compensatory movement oi the latter due to variations to the longitudinal disposition of the connecting rod IT during the adjustment of the operating mechanism, in the manner to be described.

The connection and arrangement of the connecting rod II with the actuating member I2 and with the shutter 4 is such that when the valve stem 9 is turned the usual quarter turn in the clockwise direction to shut off the gas supply, the shutter 4 will be shifted to the closing position and direction, as shown in Figures 1 and 2.

' In like manner, when the valve stem is turned in the counter-clockwise direction to open the valve to supply gas, the shutter 4 will be simultaneously shifted to the opening position to supply air. By adjusting the actuating member l2 on the valve stem 9, the operations of the shutter 4 may be varied to supply the volume of air to the gas that is mostconduciv to efiicient and economical combustion.

The pivotal connection of the shutter 4 on the mixing chamber 2 by the pivoting screw 5 is pref-- erably comparatively loose, so no friction is established between the contacting faces of the mixing chamber 2 and the shutter 4, whereby the latter is suitably free to shift to any adjusting position on its pivotal connection without encountering any frictional resistance or retardation.

In the modified form of operating mechanism, illustrated in Figures 4 and 5, the mixing'tube 7 2| is provided with a rounded mixing chamber 22 having an air opening 23 in the side wall thereof. A shutter 24, shaped to conform to the curvature of the side wall of the mixing chamber 22 is shiftably mounted for circumferential adjustment on and against said side wall, and is carried at the inner end of a supporting arm 25. The latter is provided with a hub 26 mounted on the valve stem 21 of the gas control valve 28 and being secured to said valve stem by a set screw 29. The inner end of the shutter 24 is preferably formed with an elongated slot 30 through which extends a screw 3| fiXed in the side wall of the mixing chamber 22 for stabilizing the movement of the shutter against said side wall. It will be apparent that the adjustment of the gas control Valve 28 by the partial rotation of the valve stem 27 will simultaneously adjust the shutter 24 relatively to the air opening 23 to regulate the air supply through the latter.

It will here be noted that if for any reason it is desired to operate the gas valve without the air control, it is only necessary to release the set screw securing the hub to the valve stem and tighten the screw connecting the shutter to the mixing chamber side wall, in respective embodiments herein disclosed.

The present invention provides a most eflicient device of its kind, which may be successfully employed for automatically and simultaneously regulating the air supply by the adjustment of the associated gas control valve, to thereby provide an economical burner best adapted for most efficient combustion.

What I claim is:

In a gas and air control for a gas burner, the combination of a fuel mixing tube provided with a flat top having an air opening, a substantially triangularly-shaped shutter for the latter, a screw pivotally connecting the inner end of said shutter with said top, a gas control valve extend ing into said'tube and including an outwardly projecting valve stem, a cam flange formed with a cam slot secured to said stern and being curved concentrically with respect to the axis of the latter, a bearing swivelly mounted on said valve;

and a connecting rod longitudinally slidable' in said bearing, one end of said rod being shiftably engaged in said slot and the other end thereof being pivotally joined with said shutter at a point adjacent to and eccentrically offset relatively to the screw connecting said shutter with said top. ROBERT A. CARROLL. 

